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101.
O. Das U. Aybarc Y. Yucel Ozturk B. Goren Kiral H. Ozturk Z. Kiral B. Uyulgan 《Materialwissenschaft und Werkstofftechnik》2023,54(1):109-119
This study reports the results of a preliminary study of manufacturing aluminum–potassium feldspar metal matrix composites including its castability and mechanical properties. The material was composed considering 0.25 %, 0.5 %, and 0.75 % additive ratios to examine the impact of the amount of potassium feldspar on the material and mechanical properties of the manufactured aluminum metal matrix composite material. Aluminum alloy (A356) was utilized as the matrix of the composition. The composite material was manufactured by the stir casting technique. The modulus of elasticity, yield strength, tensile strength, elongation, density, and quality index of the material parameters was taken into account to determine the materials′ practicality. The preliminary results indicated that potassium feldspar is a promising mineral to be utilized as an additive for aluminum metal matrix composites since it has a positive impact on mechanical properties. By optimizing the casting parameters, the positive aspects of the potassium feldspar may make the material more practical to be utilized in vast engineering applications. 相似文献
102.
Konstantoudakis Konstantinos Breitgand David Doumanoglou Alexandros Zioulis Nikolaos Weit Avi Christaki Kyriaki Drakoulis Petros Christakis Emmanouil Zarpalas Dimitrios Daras Petros 《Multimedia Tools and Applications》2022,81(9):12211-12250
Multimedia Tools and Applications - Immersive 3D media is an emerging type of media that captures, encodes and reconstructs the 3D appearance of people and objects, with applications in... 相似文献
103.
Describes the long-term treatment program and follow-up of a case of chronic, severe, multiple self-injurious behavior. The intensity, frequency, and multiplicity of self-injurious behavior in a boy 1st seen at age 61/2 yrs is unparalleled in the literature. Treatment spanned 10 mo and more than 1,000 therapy hrs. Contingent electric shock and differential reinforcement of other behavior were the primary techniques utilized. The specifics of the punishment and reinforcement contingencies were modified throughout the program as a function of the behavior, thereby allowing for evaluation of the various components of the treatment procedures. Although initial results were only partially successful, total suppression was eventually achieved in the laboratory setting. The procedures described for extending this control to the natural environment proved only moderately successful. The technical, ethical, and theoretical issues concerning the treatment of severe self-injurious behavior are discussed. It is suggested that the extrapolation of laboratory evidence to the natural setting is premature in the case of severe self-injurious behavior. Suggested criteria for the assessment of successful clinical treatment of self-injurious behavior are offered. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
I
— an interactive program for calibrating activated sludge systems is formulated and demonstrated. The model involves a heuristic screening algorithm for exploring the system equations structure, analytical computations of the sensitivities of the variables to the model coefficients, analytical computations of the gradients of the objective functions selected for the calibration process, and a gradient interactive steepest descent minimization scheme. The methodology was implemented in an end-user PC program: I
, that uses the TK S
® and M
® as computational engines, and
as the shell. Applications to the activated sludge system models of (Argaman Water Research 29(1) and Argaman et al. (Journal of Environmental Engineering ASCE 125(7) (1999), 608-617) are presented. 相似文献
105.
106.
The current emphasis in nursing is on caring, what it involves and why it is the profession's responsibility. This article focuses on the opposite behaviors--the "dark side of nursing" (Jameton, 1992). By developing a fuller understanding of nurse behaviors labeled the "dark side of nursing," the profession can better comprehend what caring involves and develop innovative ways to reduce dark-side behaviors. Although marginalizing, labeling and stereotyping, and stigmatizing are related, the focus will be on stigmatizing responses to patients. A number of investigators document nurse stereotyping of suicidal patients, persons with AIDS, racial/ethnic groups, and sex offenders and the impact on patients. Social psychological theories on stereotyping and deviant behavior provide some explanation for the nurse's behavior. The organizational perspective, however, has not been employed to enhance our understanding of nor to eliminate this phenomenon. Combining an organizational perspective with the social psychological theory of negative stereotyping (stigmatizing) and philosophical theory involving ethics provides a more comprehensive theory for understanding the "dark side of nursing" and designing interventions to reduce the occurrence of this damaging behavior. 相似文献
107.
Ma. de Guadalupe Garcia-Hernandez Jose Ruiz-Pinales Eva Onaindia J. Gabriel Aviña-Cervantes Sergio Ledesma-Orozco Edgar Alvarado-Mendez Alberto Reyes-Ballesteros 《Artificial Intelligence Review》2012,37(2):157-167
The problem of solving large Markov decision processes accurately and quickly is challenging. Since the computational effort
incurred is considerable, current research focuses on finding superior acceleration techniques. For instance, the convergence
properties of current solution methods depend, to a great extent, on the order of backup operations. On one hand, algorithms
such as topological sorting are able to find good orderings but their overhead is usually high. On the other hand, shortest
path methods, such as Dijkstra’s algorithm which is based on priority queues, have been applied successfully to the solution
of deterministic shortest-path Markov decision processes. Here, we propose an improved value iteration algorithm based on
Dijkstra’s algorithm for solving shortest path Markov decision processes. The experimental results on a stochastic shortest-path
problem show the feasibility of our approach. 相似文献
108.
Avi Lerner Drashti Kewada Ayan Ahmed Kate Hardy Mark Christian Stephen Franks 《International journal of molecular sciences》2021,22(1)
Polycystic ovary syndrome (PCOS) is a common endocrinopathy that is associated with an adverse metabolic profile including reduced postprandial thermogenesis. Although abnormalities in adipose tissue function have been widely reported in women with PCOS, less is known about direct effects of androgen on white and, particularly, brown adipocytes. The purpose of this study was to investigate the effect of the nonaromatizable androgen dihydrotestosterone (DHT) on (1) lipid accumulation and expression of adipogenic markers in immortalized mouse brown adipose cell lines (IMBATs), (2) mitochondrial respiration in IMBATs, (3) mitochondrial DNA content and gene expression, (4) expression of brown adipose tissue (BAT) markers and thermogenic activation. In addition, we profiled the relative levels of 38 adipokines secreted from BAT explants and looked at androgen effects on adipokine gene expression in both IMBATs and immortalized mouse white adipose (IMWATs) cell lines. Androgen treatment inhibited IMBAT differentiation in a dose-dependent manner, reduced markers of adipogenesis, and attenuated the β-adrenoceptor-stimulated increase in uncoupling protein-1 (UCP1) expression. In explants of mouse interscapular BAT, androgen reduced expression of UCP1, peroxisome proliferator-activated receptor-γ coactivator-1 (PCG-1) and Cidea. Significantly, as well as affecting genes involved in thermogenesis in BAT, androgen treatment reduced mitochondrial respiration in IMBATs, as measured by the Seahorse XF method. The results of this study suggest a role for excess androgen in inhibiting brown adipogenesis, attenuating the activation of thermogenesis and reducing mitochondrial respiration in BAT. Together, these data provide a plausible molecular mechanism that may contribute to reduced postprandial thermogenesis and the tendency to obesity in women with PCOS. 相似文献
109.
A + 20 dBm power amplifier (PA) for applications in the 60 GHz industrial scientific medical (ISM) band is presented. The PA is fabricated in a 0.13-mum SiGe BiCMOS process technology and features a fully-integrated on-chip RMS power detector for automatic level control (ALC), built-in self test and voltage standing wave ratio (VSWR) protection. The single-stage push-pull amplifier uses center-tapped microstrips for a highly efficient and compact layout with a core area of 0.075 mm2. The PA can deliver up to 20 dBm, which to date, is the highest reported output power at mm-wave frequencies in silicon without the need for power combining. At 60 GHz it achieves a peak power gain of 18 dB, a 1-dB compression (P1dB) of 13.1 dBm, and a peak power-added efficiency (PAE) of 12.7%. The amplifier is programmable through a three-wire serial digital interface enabeling an adaptive bias control from a 4-V supply. 相似文献
110.
Avi Rotem Jose C. Merchuk Shoshana Arad 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1992,55(3):263-267
The unicellular red alga Porphyridium sp. was cultured in a medium to which increasing concentrations of its cell wall polysaccharide were added. As the polysaccharide concentration in the culture medium increased, algal growth rate and maximum cell number progressively decreased. In a different series of experiments it was shown that the polysaccharide also inhibited the rate of carbon uptake by the cells and as a result photosynthesis was also inhibited. In-vitro experiments showed that the mass transfer coefficient for nitrate, bicarbonate, phosphate and potassium decreased as the polysaccharide concentration increased. The data indicate that the polysaccharide inhibits nutrient transfer from the medium to the cells, resulting in a reduction of the growth rate. 相似文献