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11.
I have discussed a model of the psyche comprising two different modes of thinking, one non-psychotic and the other psychotic. I have related these modes of thinking to our modern myth of Jekyll and Hyde, the study of which could in my opinion give us some insight into their nature. In my view a non-psychotic state of mind belongs to a person who has a history, with particular parents, a particular development, particular conflicts, and operates in the depressive position. A psychotic state of mind belongs to a person who lives in a still and timeless present, with no origin, no development and no conflict, and operates in the paranoid-schizoid position. On the basis of this model I have subsequently described the life history of a psychotic patient and an analytic session in detail, showing how psychotic and non-psychotic states alternate and interact with each other within the same individual and between patient and therapist. The use of my countertransference, moving from a concrete to a symbolic position, has enabled me to make an interpretation. The result of this interpretation has been double, leading to a negative therapeutic reaction. An upsurge of psychotic fury was followed by increased patient/therapist communication, with a small movement from the paranoid-schizoid to the depressive position. 相似文献
12.
Submersibles require the capability to accurately maintain their position when they are observing, photographing, or working at a site. The most direct way for an ROV or AUV to maintain position in the near bottom environment is to track or lock onto stationary objects on the ocean floor. A particular advantage of an optical stationkeeping system is its ability to use natural rather than manmade beacons. Several improvements to our previously reported optical flow methods for the detection of vehicle motion have been investigated. Experimental results indicate that an adaptation of Newton-Raphson search combined with the use of a low-noise, high accuracy camera can drastically reduce the number of image points at which computations need be made. Other experiments with an algorithm, which accounts for illumination variations that one may encounter in undersea environments, show significant improvement in the estimation of optical flow and vehicle motion. 相似文献
13.
14.
Michael Fox Richard Hastings Scott Lovald Juan Heinrich 《Journal of Failure Analysis and Prevention》2007,7(3):165-174
A failure analysis case study is presented for a two-piece aerosol containing tetrafluoroethane, commonly referred to as Refrigerant
134a. A gentleman was preparing to recharge the air conditioning system of an automobile when the bottom exploded off the
aerosol container, propelling the body of the aerosol container like a rocket, which hit the man in the eye and blinded him
in that eye. The aerosol was never connected to the air conditioner, therefore backpressure from the air conditioner (AC)
compressor was ruled out as a cause for the explosion. The objective of the study was to determine why the aerosol exploded.
Several recently developed test methods were used, including two types of heat-to-burst tests and a puncture chamber to measure
the pressure-versus-temperature behavior of aerosols. More common test methods were also used, such as water bath pressure
tests, hydro pressure burst tests, pneumatic pressure burst tests, hardness measurements, weight measurements, metallography,
scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and an accident scenario recreation. A semi-empirical
correlation between the hardness and weights of the container bottoms was used to determine the explosion temperature and/or
pressure. This semi-empirical correlation agrees in principle with an analysis of the explosion pressures using finite-element
analysis (FEA). The root cause for the explosion was determined to be a lack of strength of the bottom of the two-piece aerosol
coupled with heating the aerosol to temperatures significantly above room temperature. 相似文献
15.
16.
ME Hoatlin FE Ferro RW Geib MT Fox SL Kozak D Kabat 《Canadian Metallurgical Quarterly》1995,69(2):856-863
Although the Friend virus-encoded membrane glycoprotein (gp55) activates erythropoietin receptors (EpoR) to cause erythroblastosis only in certain inbred strains of mice but not in other species, mutant viruses can overcome aspects of mouse resistance. Thus, mice homozygous for the resistance allele of the Fv-2 gene are unaffected by gp55 but are susceptible to mutant glycoproteins that have partial deletions in their ecotropic domains. These and other results have suggested that proteins coded for by polymorphic Fv-2 alleles might directly or indirectly interact with EpoR and that changes in gp55 can overcome this defense. A new viral mutant with an exceptionally large deletion in its ecotropic domain is now also shown to overcome Fv-2rr resistance. In all cases, the glycoproteins that activate EpoR are processed to cell surfaces as disulfide-bonded dimers. To initiate analysis of nonmurine resistances, we expressed human EpoR and mouse EpoR in the interleukin 3-dependent mouse cell line BaF3 and compared the abilities of Friend virus-encoded glycoproteins to convert these cells to growth factor independence. Human EpoR was activated in these cells by erythropoietin but was resistant to gp55. However, human EpoR was efficiently activated in these cells by the same viral mutants that overcome Fv-2rr resistance in mice. By construction and analysis of human-mouse EpoR chimeras, we obtained evidence that the cytosolic domain of human EpoR contributes to its resistance to gp55 and that this resistance is mediated by accessory cellular factors. Aspects of host resistance in both murine and nonmurine species are targeted specifically against the ecotropic domain of gp55. 相似文献
17.
The measurement of neonatal responses to painful stimuli remains a significant clinical problem. Although numerous measures have been evaluated, instruments that are valid, reliable, and clinically feasible are not yet available. The purpose of this paper is to critique the studies that have been done using biochemical, physiological, and behavioral measures to evaluate neonatal responses to painful stimuli. Specific issues regarding measurement in premature and critically ill neonates are emphasized. The intent of this review and critique of the literature is to stimulate additional research into the assessment of neonatal pain. 相似文献
18.
Vector quantization by deterministic annealing 总被引:7,自引:0,他引:7
Rose K. Gurewitz E. Fox G.C. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1992,38(4):1249-1257
A deterministic annealing approach is suggested to search for the optimal vector quantizer given a set of training data. The problem is reformulated within a probabilistic framework. No prior knowledge is assumed on the source density, and the principle of maximum entropy is used to obtain the association probabilities at a given average distortion. The corresponding Lagrange multiplier is inversely related to the `temperature' and is used to control the annealing process. In this process, as the temperature is lowered, the system undergoes a sequence of phase transitions when existing clusters split naturally, without use of heuristics. The resulting codebook is independent of the codebook used to initialize the iterations 相似文献
19.
Modern bipolar junction transistors (BJTs) tend to operate with saturated carrier velocity in the collector space-charge region. A physical analysis of the effects of velocity saturation on the output resistance of BJTs, especially for high current levels is presented. Physical analyses show that when the collector current density approaches a critical value, the Early voltage can increase significantly due to carrier-velocity saturation as the resulting base push-out partially offsets base-width modulation. This effect is also demonstrated in simulations with PISCES and MMSPICE 相似文献
20.