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61.
62.
In diaphragm-based micromachined calorimetric flow sensors, convective heat transfer through the test fluid competes with the spurious heat shunt induced by the thin-film diaphragm where heating and temperature sensing elements are embedded. Consequently, accurate knowledge of thermal conductivity, thermal diffusivity, and emissivity of the diaphragm is mandatory for design, simulation, optimization, and characterization of such devices. However, these parameters can differ considerably from those stated for bulk material and they typically depend on the production process. We developed a novel technique to extract the thermal thin-film properties directly from measurements carried out on calorimetric flow sensors. Here, the heat transfer frequency response from the heater to the spatially separated temperature sensors is measured and compared to a theoretically obtained relationship arising from an extensive two-dimensional analytical model. The model covers the heat generation by the resistive heater, the heat conduction within the diaphragm, the radiation loss at the diaphragm’s surface, and the heat sink caused by the supporting silicon frame. This contribution summarizes the analytical heat transfer analysis in the microstructure and its verification by a computer numerical model, the measurement setup, and the associated thermal parameter extraction procedure. Furthermore, we report on measurement results for the thermal conductivity, thermal diffusivity, and effective emissivity obtained from calorimetric flow sensor specimens featuring dielectric thin-film diaphragms made of plasma enhanced chemical vapor deposition silicon nitride.  相似文献   
63.
Tobacco use is prevalent among youth with alcohol and other drug problems, yet this issue has received limited research and clinical attention. This study reports on a controlled evaluation of a cigarette smoking intervention with 54 adolescents in treatment for substance abuse, ages 13-18 (22% female). Participants were assessed at 4 time points. A greater proportion of participants in the treatment condition (n = 26) reported cessation attempts and point abstinence than did control participants (n = 28) at all time points. However, significant differences were found only for point abstinence at a 3-month follow-up. These findings provide initial support for the efficacy of a smoking cessation intervention delivered in the context of adolescent substance abuse treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
64.
During and after rolling or flattening of metal strips and plates the permissible deviations from flatness are described by the permissible absolute wave height and the flatness index. Both values can be determined on a measuring table while the material is not subjected to global tension. Because this procedure is expensive, time‐consuming and allows measurement only at discrete positions along the strip length, on‐line flatness measuring systems are used which can detect the distribution of longitudinal tensile stresses distributed across the strip width allowing for the calculation of the flatness index. This value does not always agree with the value obtained directly by measuring on the table even when the measurement of the longitudinal tensile stress distribution operates perfectly. It can be shown that the measurement of the tensile stress distribution does not give a direct indication on the wave height in the tension‐free state determined on the measuring table. To explain the relationship between tensile stress distribution in the strip and the flatness measurement on the measuring table, the buckling behavior is analysed both with and without dead load for simple symmetrical residual stress distributions resulting, e.g., from the rolling process. Based on the knowledge of the distribution of the longitudinal residual stresses across the strip width, the flatness index and the wave height can be determined by using a specialized finite element model. If the direct measurement is performed under action of dead load, large differences between the directly and indirectly obtained flatness index are observed. Below a certain limit of the intensity of the residual stress distribution the strips and plates lie flat on the measuring table. Above this limit the strip lying on the table exhibits post‐bucking deformations. In the latter case, the wave height increases with strip thickness and intensity of residual stresses.  相似文献   
65.
Cognitive dissonance and effects of self-affirmation on dissonance arousal were examined cross-culturally. In Studies 1 and 2, European Canadians justified their choices more when they made them for themselves, whereas Asian Canadians (Study 1) or Japanese (Study 2) justified their choices more when they made them for a friend. In Study 3, an interdependent self-affirmation reduced dissonance for Asian Canadians but not for European Canadians. In Study 4, when Asian Canadians made choices for a friend, an independent self-affirmation reduced dissonance for bicultural Asian Canadians but not for monocultural Asian Canadians. These studies demonstrate that both Easterners and Westerners can experience dissonance, but culture shapes the situations in which dissonance is aroused and reduced. Implications of these cultural differences for theories of cognitive dissonance and self-affirmation are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
66.
This special issue, entitled "Evidence-Based Parent and Family Interventions in School Psychology," examines the data that support the use of interventions as methods for changing children's school-related behavior and learning problems. Taken together, the articles reflect the work of the Parent and Family Intervention domain of the Evidence-Based Interventions in School Psychology Task Force. Across the articles in this special issue, the categories of coding criteria in the Manual were used to organize the presentation of results. Six review articles on the evidence base for parent and family intervention appear next; these are followed by commentary from distinguished scholars and a brief reflective comment from the special issue editors. Parent intervention is the exclusive focus of the reviews of parent education and parent consultation. Two reviews focus on the home-school relationship including the articles on parent involvement and home-school collaboration. Two reviews include both parent and family treatments: early childhood family-focused interventions and parent training and family systems interventions. Commentary was sought from the current co-chairs of the Task Force, an expert in evidence-based practice in child clinical psychology, a researcher in family-school linkages and parent consultation, and a methodologist. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
67.
Dynamic linking of software components   总被引:1,自引:0,他引:1  
Franz  M. 《Computer》1997,30(3):74-81
Traditionally, dynamic linkers merely combined previously compiled pieces of code. Faster processors are now making outright code generation at load time practical, leading to cross-platform portability at very little extra cost. While the central idea behind dynamic linking is quite straightforward, it can be implemented through a surprising variety of strategies. The author contrasts three simple dynamic linking schemes with two much more elaborate strategies. The latter represent a workload shift from the compiler to the dynamic linker, just as dynamic linking itself represents a shift that moves the functions of a separate linker into the loader. Because the new techniques promise the profound additional benefit of cross-platform portability, they will most likely displace the currently popular linking-loader approach  相似文献   
68.
The aims of the present study were to examine whether written emotional disclosure would reduce distress among cancer patients and whether it would buffer the effects of high levels of social constraint (negative social responses to patients' expressions of emotion regarding their cancer) on distress. Cancer patients (N=104) were randomly assigned to write about their emotions regarding their cancer 20 min a day for 3 days or to write about a nonemotional topic. They completed questionnaires at baseline and 6 months postintervention. Results showed that written disclosure buffered the effects of social constraints on stress at the 6-month follow-up and that avoidance partly mediated these effects. The present data reinforce the notion that interventions should be tailored to patients' needs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
69.
Oxidation processes can oxidize biorecalcitrant compounds into biodegradable intermediates, which in turn can be treated less expensively by a subsequent biological process. To design such a two-step (chemical+biological) process to treat poorly characterized wastewaters, it is useful to model the time evolution of characteristic global variables, chemical oxygen demand (COD) and biochemical oxygen demand (BOD), in order to develop a useful treatment strategy based upon these classical variables. We consider two simple model reaction networks, requiring three- and five-rate constants, respectively. The first model, proposed recently, involves conversion of a nonbiodegradable species, C, into a single biodegradable intermediate S. Here, biodegradable compounds are immediate kinetic products of oxidation. In general, it is not probable that a single recalcitrant compound undergoes a single-step reaction to CO2. However, when working with complex undefined wastewaters streams, single-step reactions may be used to simplify. The second new model corresponds to a lag time in BOD formation due to the necessity of multiple partial oxidations to reach a first biodegradable intermediate. The second network includes two intermediates, I and S, which are, respectively, nonbiodegradable and biodegradable. We then compare model behavior with an unfortunately sparse literature on BOD and COD values versus time in chemical reactors, and demonstrate the convenience of the first model, and the occasional necessity of the second, which reflects the presence of early intermediates which are nonbiodegradable.  相似文献   
70.
The authors compared longitudinal treatment outcomes for depressed substance-dependent veterans (N = 206) assigned to integrated cognitive–behavioral therapy plus standard pharmacotherapy (ICBT + P) or 12-step facilitation therapy plus standard pharmacotherapy (TSF + P). Drug and alcohol involvement and depressive symptomology were measured at intake and at 3-month intervals during treatment and up to 1 year posttreatment. Participants in both treatment conditions showed decreased depression and substance use from intake. ICBT + P participants maintained improvements in substance involvement over time, whereas TSF + P participants had more rapid increases in use in the months following treatment. Decreases in depressive symptoms were more pronounced for TSF + P than ICBT + P in the 6 months posttreatment. Within both treatment groups, higher attendance was associated with improved substance use and depression outcomes over time. Initial levels of depressive symptomology had a complex predictive relationship with long-term depression outcomes. Early treatment response predicted long-term substance use outcomes for a portion of the sample. Although both treatments were associated with improvements in substance use and depression, ICBT + P may lead to more stable substance use reductions compared with TSF + P. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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