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71.
72.
Blanchard Edward B.; Appelbaum Kenneth A.; Guarnieri Patricia; Neff Debra F.; Andrasik Frank; Jaccard James; Barron Kevin D. 《Canadian Metallurgical Quarterly》1988,56(3):427
Tension and vascular headache patients, initially treated with biofeedback and/or relaxation training in either a minimal therapist contact protocol (3 visits) or an intensive individual protocol (10 or 16 visits) were followed-up prospectively for 2 years. In the first study, for the first 6 months of follow-up, half of all patients continued to keep headache diaries and were seen monthly and the other half had only minimal contact. The results at 1-year follow-up, based on 4 weeks of daily headache diaries, revealed equally good maintenance from both treatment protocols and from both follow-up conditions. In Study 2, we found that patients remained improved over pretreatment baseline levels at the 2-year follow-up regardless of initial treatment intensity. Approximately three quarters of vascular patients who were initially improved at posttreatment remained improved at 2 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
Frank G. Pagan 《Software》1988,18(6):509-527
There is an effective and quite general method of manually deriving compilers from programming-language interpreters without dealing directly with machine language. The method is an implementation of the largely theoretical and under-appreciated concept of partial computation, but can be understood on its own terms. It involves the translation of a source program's intermediate form into the interpreter's implementation language. This paper shows how the method can be used to transform both a sample iterative interpreter and a sample recursive interpreter into compilers. The result can be a large gain in program execution speed. Other advantages of the method, including the ease and practicality of applying it, are discussed. 相似文献
74.
75.
H.‐G. Boyen G. Kstle K. Zürn T. Herzog F. Weigl P. Ziemann O. Mayer C. Jerome M. Mller J.P. Spatz M.G. Garnier P. Oelhafen 《Advanced functional materials》2003,13(5):359-364
Starting with Co‐salt‐loaded inverse micelles, which form if the diblock copolymer polystyrene‐block‐poly(2‐vinylpyridine) is dissolved in a selective solvent like toluene and CoCl2 is added to the solution, monomicellar arrays of such micelles exhibiting a significant hexagonal order can be prepared on top of various substrates with tailored intermicellar distances and structure heights. In order to remove the polymer matrix and to finally obtain arrays of pure Co nanoparticles, the micelles are first exposed to an oxygen plasma, followed by a treatment in a hydrogen plasma. Applying in‐situ X‐ray photoelectron spectroscopy, it is demonstrated that: 1) The oxygen plasma completely removes the polymer, though conserving the original order of the micellar array. Furthermore, the resulting nanoparticles are entirely oxidized with a chemical shift of the Co 2p3/2 line pointing to the formation of Co3O4. 2) By the subsequent hydrogen plasma treatment the nanoparticles are fully reduced to metallic Co. 3) By exposing the pure Co nanoparticles for 100 s to various oxygen partial pressures pequation/tex2gif-inf-5.gif, a stepwise oxidation is observed with a still metallic Co core surrounded by an oxide shell. The data allow the extraction of the thickness of the oxide shell as a function of the total exposure to oxygen (pequation/tex2gif-inf-7.gif × time), thus giving the opportunity to control the ferromagnetic–antiferromagnetic composition of an exchange‐biased magnetic system. 相似文献
76.
Fincham Frank D.; Beach Steven R. H.; Davila Joanne 《Canadian Metallurgical Quarterly》2007,21(3):542
Does forgiveness predict later conflict resolution in married couples? Twelve-month follow-up data on conflict resolution were collected from the couples studied by F. D. Fincham, S. R. Beach, and J. Davila (see record 2004-11293-007), who had provided earlier reports of forgiveness and conflict resolution. For wives, the positive dimension of forgiveness or benevolence predicted husbands' later reports of better conflict resolution controlling for initial levels of conflict resolution. This finding was independent of wives' marital satisfaction and the degree of hurt engendered by husbands' transgressions. For husbands, the only predictor of wives' reports of later conflict resolution was initial level of conflict resolution. The findings are discussed in terms of the direction of effect between forgiveness and conflict resolution and of the mechanisms that might link them. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
The wireless connectivity in pervasive computing has ephemeral character and can be used for creating ad hoc networks, sensor
networks, connection with RFID (Radio Frequency Identification) tags etc. The communication tasks in such wireless networks
often involve an inquiry over a shared channel, which can be invoked for: discovery of neighboring devices in ad hoc networks,
counting the number of RFID tags that have a certain property, estimating the mean value contained in a group of sensors etc.
Such an inquiry solicits replies from possibly large number of terminals n. This necessitates the usage of algorithms for resolving batch collisions (conflicts) with unknown conflict multiplicity n. In this paper we present a novel approach to the problem of collision resolution for batch conflicts. We show how the conventional
tree algorithms for collision resolution can be used to obtain progressively accurate estimation of the multiplicity. We use
the estimation to propose a more efficient binary tree algorithm, termed Estimating Binary Tree (EBT) algorithm. The EBT algorithm
is suited for implementation when the conflicting nodes are passive, such as e.g. RFID tags. We extend the approach to design
the Interval Estimation Conflict Resolution (IECR) algorithm. For n→∞ we prove that the efficiency achieved by IECR for batch arrivals is identical with the efficiency that Gallager’s FCFS
algorithm achieves for Poisson packet arrivals. For finite n, the simulation results show that IECR is, to the best of our knowledge, the most efficient batch resolution algorithm reported
to date. 相似文献
78.
Mou Weimin; Biocca Frank; Owen Charles B.; Tang Arthur; Xiao Fan; Lim Lynette 《Canadian Metallurgical Quarterly》2004,10(4):238
In 3 experiments, the authors investigated spatial updating in augmented reality environments. Participants learned locations of virtual objects on the physical floor. They were turned to appropriate facing directions while blindfolded before making pointing judgments (e.g., "Imagine you are facing X. Point to Y"). Experiments manipulated the angular difference between the learning heading and the imagined heading and between the actual heading and the imagined heading. The effect of actual-imagined on pointing latency was observed for naive users but not for users with brief training or instructions concerning the fact that objects can move with body movements. The results indicated that naive users used an environment-stabilized reference frame to access information arrays, but with experience and instruction the nature of the representation changed from an environment stabilized to a body stabilized reference frame. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
80.
Heriberto Cabezas Christopher W. Pawlowski Audrey L. Mayer N. Theresa Hoagland 《Clean Technologies and Environmental Policy》2003,5(3-4):167-180
Sustainability is generally associated with a definition by the World Commission on Environment and Development, 1987: "... development that meets the needs of the present without compromising the ability of future generations to meet their own needs ..." However, there is no mathematical theory embodying these concepts, although one would be immensely valuable in humanity's efforts to manage the environment. The concept of sustainability applies to integrated systems comprising humans and the rest of nature; the structures and operation of the human component (society, economy, law, etc.) must be such that they reinforce the persistence of the structures and operation of the natural component (ecosystem trophic linkages, biodiversity, biogeochemical cycles, etc.). One of the challenges of sustainability research lies in linking measures of ecosystem functioning to the structure and operation of the associated social system. We review the nature of this complex system including its ecological, social, economic, and technological aspects, and propose an approach to assessing sustainability based on Information Theory that bridges the natural and human systems. These principles are then illustrated using a model system with an ecological food web linked to a rudimentary social system. This work is part of the efforts of a larger multidisciplinary group at the U.S. Environmental Protection Agency's National Risk Management Research Laboratory. 相似文献